FIC 1650cc injectors idling rich on 93 octane
Aug 1, 2017, 07:18 AM
#31
EvoM Community Team Leader
Yes thats how i understand it as well, just that if that non linear region happens to be below minimum pulse width then it wont matter because the ECU cannot produce such a small pulse. Thats why you would need to change the Minimum injector pulse width setting as well if you happen to fall in that range. If after doing the linearization you don't require pulse widths smaller then the minimum then your fine and you don't have to mess with it. Depends on a lot of variables.
Aug 4, 2017, 09:24 PM
#32
Evolving Member
Thread Starter
38psi That's about what I expected it's usually 2-3 pounds higher than stock pump. No big deal if you drill the siphon I bet it drops 2-3 psi. This will bring you up .5 afr not a lot. If you tuner does the mods in the 1650 thread, linearization table. The min IPW too just set it around .900, then tune the afr around 13.5-14.5 it should start to run poorly any leaner due to injectiors response time. Back the afr down a .5 point and it's smooth as a baby's bottom. Keep you idle timing around 12 degrees.
I drilled the siphon yesterday and tested the pressure briefly tonight. It was still around 38psi maybe 37. No big changes that I saw yet. I'm going to do some more testing over the weekend and let the car warm up and try again.
Could the stock FPR have gone bad? Would replacing the return lines under the hood and the fuel housing help? I'm running all stock fuel lines right now other then the double pumper lines/filter.
Aug 4, 2017, 11:38 PM
#35
Account Disabled
Aug 5, 2017, 07:15 AM
#36
EvoM Community Team Leader
If the regulator could't handle the extra flow from a new pump at low load, then a new regulator would not be the solution. A different, higher value fuel pump resistor would be. The way the factory handles reducing flow during low load is by regulating current to the pump, not by just putting bigger fuel system components in. A new bigger regulator would work, but your still making the pump and rest of the system work harder then they should be vs just installing a different resistor.
Aug 5, 2017, 08:39 AM
#37
Evolved Member
If the regulator could't handle the extra flow from a new pump at low load, then a new regulator would not be the solution. A different, higher value fuel pump resistor would be. The way the factory handles reducing flow during low load is by regulating current to the pump, not by just putting bigger fuel system components in. A new bigger regulator would work, but your still making the pump and rest of the system work harder then they should be vs just installing a different resistor.
20 psi - 25 psi - 30 psi .. still works good.
Aug 5, 2017, 09:59 AM
#38
EvoM Community Team Leader
Aug 5, 2017, 05:12 PM
#39
Evolved Member
I drilled the siphon yesterday and tested the pressure briefly tonight. It was still around 38psi maybe 37. No big changes that I saw yet. I'm going to do some more testing over the weekend and let the car warm up and try again.
Could the stock FPR have gone bad? Would replacing the return lines under the hood and the fuel housing help? I'm running all stock fuel lines right now other then the double pumper lines/filter.
Could the stock FPR have gone bad? Would replacing the return lines under the hood and the fuel housing help? I'm running all stock fuel lines right now other then the double pumper lines/filter.
Aug 5, 2017, 05:26 PM
#40
Evolving Member
Thread Starter
38 psi is fine. Gauges don't always read the same. Your fpr is fine. Do the mods suggested and your tuner should have a much easier time getting the afr's inline. Now that you have the siphon drilled your rich spike when the second pump kicks on will be minimal. I set the Hobbs to turn on around 15psi.
An AEM fuel pressure gauge is being shipped to me. It should be more precise and make it so I can monitor while driving.
I will work on getting the patch put into the tune.
Aug 6, 2017, 06:20 AM
#43
Evolved Member